Replacement heart valves, delivery devices and methods

ABSTRACT

A replacement heart valve and method of treating valve insufficiency includes an expandable frame configured to engage a native valve annulus. A valve body is coupled to the frame. The valve body can include a leaflet portion and possibly a skirt portion. A portion of the frame has a foreshortening portion configured to longitudinally expand when urged to a radially compacted state and longitudinally contract when urged to a radially expanded state. In one embodiment the valve skirt is attached to the frame so that it can adapt to changes in the length of the frame. A delivery device in some embodiments can use one or more coverings, such as sheaths, to controllably release the replacement heart valve at a native heart valve.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/702,233, filed May 1, 2015, now U.S. Pat. No. 9,949,827, which is acontinuation of U.S. application Ser. No. 13/756,424, filed Jan. 31,2013, now U.S. Pat. No. 9,023,100, which is a continuation of U.S.application Ser. No. 13/244,080, filed Sep. 23, 2011, now U.S. Pat. No.8,652,203, which claims priority to U.S. Provisional Appl. No.61/385,651, filed Sep. 23, 2010. This application is also related toU.S. application Ser. No. 12/569,856, filed Sep. 29, 2009, No.12/761,349, filed Apr. 15, 2010, and No. 13/165,721, filed Jun. 21,2011. The entirety of each of the above applications is incorporated byreference herein and is to be considered a part of this specification.

BACKGROUND Field of the Invention

Certain embodiments disclosed herein relate generally to replacementvalves for a vascular system, delivery devices for the replacementvalves, and related delivery methods, among other things. In particular,the valves relate to replacement heart valves, such as for the mitralvalve.

Description of the Related Art

Human heart valves, which include the aortic, pulmonary, mitral andtricuspid valves, function essentially as one-way valves operating insynchronization with the pumping heart. The valves allow blood to flowdownstream, but block blood from flowing upstream. Diseased heart valvesexhibit impairments such as narrowing of the valve or regurgitation,which inhibit the valves′ ability to control blood flow. Suchimpairments reduce the heart's blood-pumping efficiency and can be adebilitating and life threatening condition. For example, valveinsufficiency can lead to conditions such as heart hypertrophy anddilation of the ventricle. Thus, extensive efforts have been made todevelop methods and apparatus to repair or replace impaired heartvalves.

Prostheses exist to correct problems associated with impaired heartvalves. For example, mechanical and tissue-based heart valve prosthesescan be used to replace impaired native heart valves. More recently,substantial effort has been dedicated to developing replacement heartvalves, particularly tissue-based replacement heart valves, that can bedelivered with less trauma to the patient than through open heartsurgery. Replacement valves are being designed to be delivered throughminimally invasive procedures and even percutaneous procedures. Suchreplacement valves often include a tissue-based valve body that isconnected to an expandable frame that is then delivered to the nativevalve's annulus.

Development of replacement heart valves that can be compacted fordelivery and then controllably expanded for controlled placement, andthe related delivery devices have proven to be particularly challenging.

SUMMARY OF THE INVENTION

Accordingly, there is in the need of the art for improved replacementheart valves, delivery devices, and delivery methods, among otherthings.

In some embodiments a replacement heart valve can comprise an expandableframe, and a valve body. The expandable frame can be configured toengage a native valve annulus, wherein the frame extends longitudinallybetween an upstream end and a downstream end, the frame having aforeshortening portion at or adjacent the downstream end, theforeshortening portion comprising foreshortening cells that arelongitudinally expanded when the frame is in a radially compacted stateand longitudinally contracted when the frame is in a radially expandedstate. The valve body can be coupled to the frame, the valve bodycoupled to the frame in the foreshortening portion in a manner so thatthe frame foreshortening portion can move longitudinally relative to thevalve body. Upon radial compaction of the implant, the frameforeshortening portion can longitudinally expand but moves relative tothe valve body so that the valve body substantially retains itslongitudinal length.

According to some embodiments, the valve body can have a downstream endthat is generally aligned with a downstream end of the frameforeshortening portion, but is not connected to the downstream end ofthe frame foreshortening portion. A first longitudinal distance canexist between the downstream end of the frame foreshortening portiondownstream end and the downstream end of the valve body when the frameis in a radially expanded configuration, and a second longitudinaldistance exists between the downstream end of the frame foreshorteningportion downstream end and the downstream end of the valve body when theframe is in a radially compacted configuration, the second longitudinaldistance being greater than the first longitudinal distance.

In some embodiments, the valve body can be slidably coupled to adownstream portion of the frame and substantially non-slidably coupledto an upstream portion of the frame. The expandable frame may furthercomprise a non-foreshortening portion at or adjacent the upstream end,the non-foreshortening portion comprising longitudinal struts. Thenon-foreshortening portion can be configured to substantially maintainits longitudinal length as between the radially compacted state and theradially expanded state. The longitudinal struts can extend upstreamfrom the foreshortening cells. The valve body can be slidably coupled toa downstream portion of the frame and substantially non-slidably coupledto an upstream portion of the frame. The valve may also further comprisea substantially inelastic band at the upstream end of the expandableframe.

In some embodiments, replacement heart valve can comprise an expandableframe configured to engage a native valve annulus, wherein the frameextends longitudinally between an upstream end and a downstream end, theframe having a foreshortening portion at or adjacent the downstream end,the foreshortening portion comprising foreshortening cells that arelongitudinally expanded when the frame is in a radially compacted stateand longitudinally contracted when the frame is in a radially expandedstate, a valve body coupled to the frame, and a support band positionedwithin the frame at the upstream end.

A delivery device for delivering a replacement heart valve according tosome embodiments can comprise an inner support for receiving areplacement heart valve, an inner retainer ring on the inner support,and an outer retainer ring to slidably engage the inner retainer ring tosecure a proximal end of the replacement heart valve on the deliverydevice.

Some embodiments of delivery device can further include a floatingsheath to slidably cover a central region of the replacement heart valvebetween the proximal end and a distal end while the replacement heartvalve is in a radially compacted state and/or an outer sheath toslidably cover the replacement heart valve in the radially compactedstate, as well as the outer retainer ring, the inner retainer ring, andfloating sheath, wherein the floating sheath is connected to the outersheath with one or more tension members such that withdrawal of theouter sheath from covering the replacement heart valve can also causethe floating sheath to withdraw from covering the replacement heartvalve. The outer sheath may have a first withdrawal position where atleast the distal end of the replacement heart valve is uncovered and thefloating sheath remains covering the central region. The outer sheathmay have a second withdrawal position where the floating sheath does notcover the central region.

A method of treating valve insufficiency of a mitral valve of a patientby delivering a replacement valve can comprise one or more of thefollowing steps. Providing a replacement valve mounted on a deliverydevice, the replacement valve comprising a radially expandable framehaving an upstream end and a downstream end, the frame furthercomprising a plurality of first anchors directed toward the upstreamend. Delivering the replacement valve to a native mitral valve annuluswhile the replacement valve is in a radially compacted state, the nativemitral valve annulus having two or more native valve leaflets.Positioning the replacement valve so that tips of the plurality of firstanchors are downstream of the native valve leaflets. Exposing a portionof the downstream end of the replacement valve so that the plurality offirst anchors extend radially from the delivery device and the anchortips are positioned to an outer side of the native leaflets. Moving thereplacement valve in an upstream direction so that tips of the pluralityof first anchors engage a downstream side of the native mitral valveannulus. After the plurality of first anchors engage the native mitralvalve annulus, releasing the replacement valve from the delivery deviceand allowing the frame to expand to a radially expanded state.

In some embodiments, a method may also include one or more of thefollowing steps. Wherein the downstream end of the frame has aforeshortening portion configured to longitudinally expand when in theradially compacted state and longitudinally contract when theforeshortening portion is in the radially expanded state and theupstream end maintains a substantially constant longitudinal length inthe expanded state and in the compacted state. Wherein a downstreamportion of the frame foreshortens and flares radially outward as theframe expands to the expanded state. Wherein moving the replacementvalve in an upstream direction comprises engaging and compacting orfolding the native valve leaflets with the plurality of first anchors.Wherein moving the replacement valve in an upstream direction so thattips of the plurality of first anchors engage a downstream side of thenative valve annulus comprises engaging a posterior leaflet. Afterengaging the posterior leaflet repositioning the replacement valve, andengaging an anterior leaflet with the plurality of first anchors.Engaging an upstream side of the native mitral valve annulus with aplurality of second anchors. Exposing a portion of the downstream end ofthe replacement valve so that the plurality of first anchors extendradially from the delivery device further comprises expanding the frameto a first expanded state. Expanding the frame to a second expandedstate and moving the replacement valve in an upstream direction so thattips of the plurality of first anchors engage another part of thedownstream side of the native mitral valve annulus. Wherein releasingthe replacement valve from the delivery device and allowing the frame toexpand to a radially expanded state comprising expanding the frame to athird expanded state.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages are described belowwith reference to the drawings, which are intended to illustrate but notto limit the invention. In the drawings, like reference charactersdenote corresponding features consistently throughout similarembodiments.

FIG. 1 is a perspective view of one embodiment of a replacement heartvalve.

FIG. 2 is a view looking upstream through the replacement heart valve ofFIG. 1.

FIG. 3 is a schematic detail side view of the replacement heart valve ofFIG. 1.

FIG. 4 shows a schematic detail side view of another embodiment of areplacement heart valve.

FIG. 5A is a perspective view of a replacement heart valve in anexpanded state in accordance with an embodiment.

FIG. 5B is a side view of the replacement heart valve of FIG. 5A in acompacted state.

FIG. 5C is a side view of a portion of the cells of the compacted-statereplacement heart valve of FIG. 5B.

FIG. 5D is a side view of a portion of the cells of the expanded-statereplacement heart valve of FIG. 5A.

FIG. 6A is a perspective view of a replacement heart valve in anexpanded state in accordance with an embodiment.

FIG. 6B is a side view of the replacement heart valve of FIG. 6A in acompacted state.

FIG. 7A is a perspective view of a replacement heart valve in anexpanded state in accordance with another embodiment.

FIG. 7B is a side view of the replacement heart valve of FIG. 7A in acompacted state.

FIG. 7C is a cross-section side view of a portion of the expanded-statereplacement heart valve of FIG. 7A.

FIG. 8 schematically shows a replacement heart valve as in FIGS. 1-2deployed in a native mitral annulus of a human heart.

FIG. 9A shows an embodiment of a delivery device for delivering areplacement heart valve in accordance with one embodiment.

FIG. 9B shows a distal portion of the delivery device of FIG. 9A with aschematic representation of a valve frame.

FIGS. 10A-C schematically show a replacement heart valve and steps of amethod of deploying the replacement heart valve according to oneembodiment.

FIG. 11 shows a distal portion of another embodiment of delivery devicewith a schematic representation of a valve frame.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present specification and drawings provide aspects and features ofthe disclosure in the context of several embodiments of replacementheart valves, delivery devices and methods that are configured for usein the vasculature of a patient, such as for replacement of naturalheart valves in a patient. These embodiments may be discussed inconnection with replacing specific valves such as the patient's aorticor mitral valve. However, it is to be understood that the features andconcepts discussed herein can be applied to products other than heartvalve implants. For example, the controlled positioning, deployment, andsecuring features described herein can be applied to medical implantsfor use elsewhere in the body, such as within a vein, or the like. Inaddition, particular features of a valve, delivery device, etc. shouldnot be taken as limiting, and features of any one embodiment discussedherein can be combined with features of other embodiments as desired andwhen appropriate.

With initial reference to FIGS. 1 and 2, an embodiment of a replacementheart valve 10 is shown. The illustrated replacement heart valve 10 isdesigned to replace a damaged or diseased native heart valve such as amitral valve. The replacement heart valve 10 includes a self-expandingframe 20 to which a plurality of valve leaflets 12 are attached.

The plurality of valve leaflets 12 can function in a manner similar tothe natural mitral valve, or to other valves in the vascular system. Theplurality of valve leaflets 12 can open in a first position and thenengage one another to close the valve in a second position. Theplurality of valve leaflets 12 can be made to function as a one wayvalve such that flow in one direction opens the valve and flow in asecond direction opposite the first direction closes the valve. Thereplacement heart valve 10 can be constructed so as to open naturallywith the beating of the heart. For example, the plurality of valveleaflets 12 can be open during diastole and closed during systole. Thevalve can include many different components as will be discussed indetail below.

To aid in the description of the replacement heart valve 10, certaindirectional or relative terms may be used herein. The illustratedreplacement heart valve 10 is a one-way valve, thus the term “upstream”refers to the end or section closest to the inflow of blood or otherfluid into the valve and “downstream” refers to the end or sectionclosest to the outflow of blood or other fluid from the valve. As willbe described, the replacement heart valve 10 is generally implanted bymoving the replacement heart valve 10 within a vessel towards thediseased or damaged native valve with the flow of fluid. Thus, the term“proximal” coincides with upstream and “distal” coincides withdownstream. It should be understood that the valve can also be implantedby moving the replacement heart valve in the opposite direction. Theterm “longitudinal” refers to a direction, length or a location betweenthe proximal end 14 and the distal end 16 of the replacement heart valve10. The term “lateral” refers to a direction, length or locationperpendicular to the longitudinal direction, length or location.

Still referring to FIG. 1, the shape of the illustrated replacementheart valve 10 can be generally referred to as having an upstreamportion 38, a transition portion 40 and a downstream portion 42. Thereplacement heart valve 10 can be generally cylindrical in thelongitudinal direction with the same or a varying diameter or outerperimeter. In the illustrated embodiment, the upstream portion 38 has aninflow diameter at the proximal end 14 and the downstream portion 42preferably has an outflow diameter at the distal end 16. The upstreamportion 38 and downstream portion 42 are generally cylindrical based oneither the inflow diameter or the outflow diameter. As the outflowdiameter is greater than the inflow diameter, a generally conicaltransition portion 40 is positioned between the proximal 14 and distal16 ends. It will be understood that, in some embodiments, thereplacement heart valve 10 may not have a transition portion 40, or thatthe transition portion 40 may be very abrupt and short. In addition, insome embodiments the transition portion 40 may be coextensive witheither or both of the upstream portion 38 and the downstream portion 42.Some embodiments have a larger inflow dimension than the outflowdimension. In addition, in some embodiments the geometry of thereplacement heart valve 10 can include one or more portions that areconical, spherical, parabolic, oval, convex, concave, or the like, orany combination thereof.

Finally, a non-foreshortening portion 52 and a foreshortening portion 54are also referenced with the illustrated replacement heart valve 10. Aswill be described in more detail below, foreshortening refers to theidea that as the replacement heart valve 10 changes from the compactedor collapsed position to the expanded position the longitudinal lengthof the replacement heart valve 10 decreases in the foreshorteningportion 54 but not in the non-foreshortening portion 52.

Replacement Heart Valve Frame

As has been mentioned, the replacement heart valve 10 includes aself-expanding frame 20 to which a plurality of valve leaflets 12 areattached. Other components of the valve may also be attached to theframe 20. It is to be understood that some embodiments may not employ aself expanding frame but may, for example, employ a balloon or the liketo expand and deploy the frame.

The frame 20 can serve one or more different and unique purposes. Forexample, the frame 20 can serve as structural support for the valve, ananchoring mechanism to attach the valve to the vasculature, anattachment device to attach valve components to, a device to facilitatedelivery of the valve and a device to maintain position of the valveafter delivery.

The frame 20 can be made of many different materials, but is preferablymade from metal. For example, the frame 20 can be a wireframe or a metaltube that has been cut or etched to remove all but a metal skeleton. Theframe 20 can be constructed from a metal tube, such as a nitinol tube.In some embodiments, the frame 20 can be made from a shape memorymaterial. The frame 20 can further be expanded and/or compressed and/orotherwise worked to have the desired introduction and implantationconfigurations.

As can be seen with particular reference to FIG. 1, the frame 20includes a number of struts or members that collectively make up theframe 20. These struts can include longitudinal struts 56 and undulatingstruts, such as undulating struts forming one or more rings 58, 60, 62,64, and 66. It will be understood that the frame 20 can include anynumber of longitudinal struts, undulating struts, and rings. Theupstream 38, transition 40 and downstream 42 portions may all includemore or less longitudinal struts, undulating struts, and rings thanthose shown herein, as well as, other configurations of the same.

As mentioned previously, the replacement heart valve 10 has anon-foreshortening portion 52 and a foreshortening portion 54. Theseportions can be defined by the frame 20 and the positioning of varioustypes of struts along the frame 20. Referring now to FIGS. 1 and 3, itcan be seen that the longitudinal struts 56 span the length of thenon-foreshortening portion 52. Distal or downstream portions of thelongitudinal struts 56 make up the transition portion 40, in which thestruts 56 bend at bending stage 30 so as to flare radially outwardly andthen bend again at bending stage 32 so as to stop expanding in radiusand attach to the foreshortening portion 54 of the frame 20. As such,the frame 20 is generally divided into the upstream portion 38 made upof the first diameter, the transition portion 40 at which the diameteris expanding, and the downstream portion 42 with the larger seconddiameter. The downstream portion 42 also includes the foreshorteningportion 54.

First 58, second 60, and third 62 rings made up of undulating struts areconnected to the longitudinal struts 56 in the non-foreshorteningportion 52. The illustrated first 58 and second 60 rings are ofgenerally the same size, however, the struts in the third ring 62 aresubstantially larger and longer than the struts in the first 58 andsecond 60 rings. For example, the struts of the first 58 and second 60rings can be about half as long as the struts of the third ring 62, orshorter. Additionally, upstream anchors 22 extend from the free apicesof the struts in the third ring 62. As best shown in FIG. 3, the strutsin the third ring 62 preferably are flared radially out at a moredramatic angle than is the longitudinal strut 56 at the transitionportion 40. In the illustrated embodiment, the third ring struts 62 canbe considered part of the upstream anchors 22.

Referring to FIGS. 1 and 3, a fourth ring 64 is attached to the distalend of the longitudinal struts 56 at an apex of the fourth ring 64. Afifth ring 66 attaches to the fourth ring 66 on the side opposite thelongitudinal struts 56. The fifth ring 66 can be a mirror image of thefourth ring 64. In some embodiments, additional rings of undulatingstruts can be included in any part of the frame. For example, sixthand/or seventh rings can be positioned downstream of the fifth ring.

The fourth 64 and fifth 66 rings are made up of undulating struts andcan make up the foreshortening portion 54. Expansion of the replacementheart valve 10 causes the struts of the fourth ring 64 to move fartherapart such that they are at a greater angle relative to one another.Thus, they move from a relatively vertical orientation to a morehorizontal orientation. This also causes the ring to shrink in verticalheight. The fifth ring exhibits similar behavior when the valve 10expands. This movement of the fourth 64 and fifth 66 rings results inforeshortening of the frame 20.

Opposing anchors 22, 24 can be constructed on the frame 20 so thatpreferably their tips 26, 28 move closer together as the frameforeshortens. This can allow the anchors 22, 24 to grasp opposite sidesof the native mitral annulus or any other tissue that is perpendicularto the axis of the frame.

The anchors 22, 24 and anchor tips 26, 28 can be located anywhere alongthe frame 20 just so long as at least one of the anchors is connected tothe foreshortening portion 54 to thereby move with the foreshorteningportion 54. As shown, both of the anchor tips 26, 28 are located in theforeshortening portion 54. The foreshortening portion can also bepositioned anywhere along the frame.

Preferably, each of the anchors 22, 24 also extends generally radiallyoutwardly from the frame 20 so that the anchor tips 26, 28 are generallyspaced away from the rest of the frame 20. In some embodiments, all orpart of the structure connected to the anchor tip and extending radiallyfrom the frame, including one or more rings and/or struts, can beconsidered part of the anchor. The anchors can include a base located onthe anchor on a side opposite the tip. The base can be for example wherethe anchor begins to extend from or away from the frame 20.

In some embodiments, each of the anchors can extend radially outwardlyfrom the frame at an anchor base and terminate at an anchor tip. Theanchors can be connected to the frame at one of many different locationsincluding apices, junctions, other parts of struts, etc. The anchors cancomprise first, second, third, or more spaced apart bending stages alongthe length of each anchor. The anchors can also extend either upstreamor downstream before and/or after one or more of the bending stages. Aportion of the anchor may extend with the frame before any bendingstages. An example anchor can include first and second bending stageswith a portion between the second bending stage and the anchor tip beinggenerally parallel to an axis of the frame. Another example, can includefirst, second and third spaced apart bending stages, and wherein in thefirst bending stage the anchor is bent radially inwardly, in the secondbending stage the anchor is bent radially outwardly, and in the thirdbending stage the anchor is bent radially inwardly. In the secondbending stage the anchor can be bent about 180 degrees.

In preferred embodiments, the replacement heart valve 10 may be deployedinto a heart valve annulus, and positioned when compacted so that theanchor tips 26, 28 of the opposing anchors 22, 24 are disposed onopposite sides of the native annulus. As the replacement heart valve 10is expanded, the opposing anchors are drawn closer together so as tograsp opposite sides of the native annulus with the anchor tips 26, 28and securely hold the replacement heart valve 10 in position. As such,the replacement heart valve 10 can be held securely in position withoutrequiring a substantial radial force against the native annulus. Theforeshortening portion 54 can be used to move the anchor tips 26, 28closer together as the replacement heart valve 10 moves to the expandedposition to thereby engage the native valve annulus.

Notably, in this embodiment the native annulus which is intended to begripped between the anchor tips 26, 28 will be engaged by theforeshortening portion 54 of the frame 20, and will not engage thetransition portion 40 of the frame 20. Rather, in a mitral placement,the upstream 38 and transition 40 portions of the replacement valve 10will not necessarily be disposed within the annulus but mostly orentirely in the atrium.

Applicant's U.S. patent application Ser. No. 12/084,586, which waspublished on Aug. 27, 2009 as U.S. Publication No. 2009/0216314,discusses embodiments of foreshortening stents with anchors, and can bereferred to for further discussion of certain aspects of the illustratedembodiments. Applicant's U.S. patent application Ser. No. 13/165,721,filed on Jun. 21, 2011, discusses embodiments of foreshortening frameswith anchors, and can be referred to for further discussion of certainaspects of the illustrated embodiments. The above applications areincorporated in their entirety by reference herein with particularreference to the discussion concerning structure and operation ofembodiments of foreshortening structures, particularly foreshorteningstructures having anchors.

Replacement Heart Valve Body

The replacement heart valve can include a valve body that is made up ofone or more components. In some embodiments, the valve body onlyincludes a plurality of valve leaflets. In other embodiments, the valvebody may also include one or more of an outer valve skirt, a connectionskirt, and a support band.

As has been mentioned, a plurality of valve leaflets 12 are attached tothe self-expanding frame 20 (FIGS. 2 and 3). The plurality of valveleaflets 12 can function in a manner similar to the natural mitral valveto open and close as appropriate and thereby control blood flow.

The leaflets 12 can be one of many different shapes and configurations.There can be two, three or more leaflets 12. The leaflets 12 can be cutfrom a flat, tissue material such as pericardium. Preferably, upstreamportions of the leaflets are generally curved. The curvature and size ofthe pattern cuts, and particularly the curvature of the side edges, canbe chosen so that the valve fits within the particular shape defined bythe frame 20.

The leaflets 12 can also be positioned in any portion of the frame. Theleaflets 12 can be positioned solely within any one of the upstreamportion 38, the transition portion 40, and the downstream portion 42.The leaflets can also extend between different diameter sections of theframe 20. Looking to FIG. 3, it can be seen that in some embodiments,the leaflets 12 extend from the upstream portion 38 to the end of thetransition portion 40. The 12 leaflets 12 can alternatively extend fromany part of one of the upstream portion 38, the transition portion 40,and the downstream portion 42 to any part of one of the upstream portion38, the transition portion 40, and the downstream portion 42.

In some embodiments, the leaflets 12 can be coupled to the outwardlyflaring portion of the valve skirt 18 in the transition portion 40. Inthis position, the leaflets can be at least partially within the nativemitral valve annulus upon deployment, closer to the left ventricle, andcloser to a native leaflet position.

The replacement heart valve 10 can further include an outer valve skirt18. The outer valve skirt 18 can be configured to direct fluid to thevalve leaflets 12. The outer valve skirt 18 can also be used atpartially to control how fluid flows through and/or around thereplacement heart valve 10. The outer valve skirt 18 can surround atleast a portion of the valve and be connected to the valve leaflets 12.In some embodiments, the outer valve skirt 18 can form an inner wallconnected to and positioned within the frame 20.

The outer valve skirt 18 can extend the length of the frame 20 or it canextend along only part of the length of the frame 20. In someembodiments, the ends 14, 16 of the replacement heart valve 10 cancoincide with the inflow 34 and outflow 36 ends of the outer valve skirt18. In the illustrated embodiment of FIGS. 1-3, the inflow end 34substantially coincides with one end 14 of the replacement heart valve10 while the other end 16 of the replacement heart valve 10 extends pastthe outflow end 36 of the valve body.

The shape of the outer valve skirt 18 can substantially correspond tothat of the frame 20, with for example, different diameter sections anda transition between them. Other shapes and configurations can also beused.

The valve leaflets 12 can extend along all or part of the length of theouter valve skirt 18, and including all or part of the reduced andincreasing diameter portions, i.e., the upstream 38 and transition 40portions, as shown. In some embodiments, the leaflets 12 can also spanall or part of the length of the downstream portion 42, together with orseparate from the outer valve skirt 18.

In the illustrated embodiments, the outer valve skirt 18 is attached tothe frame 20 and the leaflets 12 are attached to the outer valve skirt18. Preferably, the outer valve skirt 18 is also formed of a pericardiumtissue similar to the leaflets 12.

The outer valve skirt 18 can be constructed in multiple different ways.For example, the outer valve skirt 18 can be made by cutting out one ormore pieces from flat tissue material and sewing the tissue together toform the outer valve skirt with a flared transition portion. Preferably,the outer valve skirt 18 is constructed of a tissue that is flexible,but not particularly expansive and stretchy.

As best shown in FIGS. 1-3, the replacement heart valve 10 can alsoinclude a connection skirt 50. The connection skirt 50 can be attachedto one or both of the frame 20 and the outer valve skirt 18. Theconnection skirt 50 can function and/or provide benefits similar to theouter valve skirt 18. For example, the connection skirt 50 can be usedto direct fluid flow into, out of, and/or around the replacement heartvalve 10. The connection skirt 50 can also be made to move with theforeshortening portion 54 of the frame 20.

The connection skirt 50 can be made of knit polyester or anotherstretchable or flexible fabric. In some embodiments, the connectionskirt 50 is made from a material that is more flexible than the outervalve skirt material and/or the valve leaflet material.

As shown, the connection skirt 50 is sewn to the outflow end 36 of theouter valve skirt 18 and is also attached to the frame 20 in theforeshortening portion. The upstream edge of the connection skirt 50 isgenerally straight so as to correspond to the downstream edge or outflowend 36 of the outer valve skirt 18 and contribute to an advantageousseam structure. The downstream end of the connection skirt 50 can bestraight, curved, or have any other desired configuration. For example,the connection skirt 50 is shown with undulations patterned to generallycorrespond to the undulations at the end 16 of the frame 20. It is to beunderstood that other configurations of the connection skirt 50 can alsobe employed.

The replacement heart valve 10 can also include a support band 44. FIG.4 illustrates a detail view of another embodiment of a replacement heartvalve 10′ including a support band 44. Numerical reference to componentsis the same as previously described, except that a prime symbol (′) hasbeen added to the reference. Where such references occur, it is to beunderstood that the components are the same or substantially similar topreviously-described components.

The support band 44 may be placed or positioned around or within theframe 20′ at the proximal end. The support band 44 can be used toreinforce and/or constrain the frame 20′. The support band 44 can helpto control the expansion of the frame 20′ from the compacted to theexpanded state. The support band 44 can also be used to reduce theamount of motion that occurs at the upstream portion 38′ and/or at theproximal end 14′ after the replacement heart valve 10′ has beenimplanted within the mitral heart valve or other location.

In some embodiments, the support band 44 may comprise a polyester fabricband. The support band 44 may comprise a no-stretch or limited stretchmaterial. Preferably the support band 44 is not made of an elasticmaterial or a material known to have high elasticity. In someembodiments, the support band 44 is made from a material that is lessflexible than the outer valve skirt material and/or the valve leafletmaterial. The distal and proximal ends of the support band 44 can bestraight, curved, undulating with the undulations of frame, or any otherdesired configuration.

The support band 44 can be connected to the valve frame with a pluralityof stitches, loops, knots, staples, or other types of connections. Insome embodiments, the frame 20′ can be sandwiched between two sides orlayers of the support band 44. Preferably, the support band 44 is asingle layer positioned within and attached to the frame 20′ with aplurality of stitches around one or more of the longitudinal and/orundulating struts.

Viewing FIG. 4 in comparison to FIG. 3, it can be seen that the leaflets12′, 12 are positioned lower in the valve, or closer to the proximal end14′, 14 in FIG. 4. The support band 44 can reduce the movement and themoment at the proximal end 14′ allowing the valve to function moresmoothly.

Still referring to FIG. 4, it can also be seen that this embodiment doesnot include a connection skirt so that the distal end 36′ of the outervalve skirt 18′ extends to the distal end 16′ of the valve.

The replacement heart valve 10′ may include a first ring of undulatingstruts in the upstream portion 38′, and a second ring of undulatingstruts in the transition portion 40′, including part of the anchor 22′.Third, fourth, and fifth rings are preferably located in the downstreamportion 42′ forming two rows of adjacent diamond- or oval-shaped cells.In some embodiments, the downstream anchors 24′ extend from the junctionof the fourth and fifth rings.

Additional example replacement heart valves with valve bodies arediscussed in detail in U.S. application Ser. Nos. 12/569,856, filed Sep.29, 2009 and 13/165,721, filed Jun. 21, 2011, both of which areincorporated by reference herein in their entirety and are to beconsidered a part of this specification.

Expansion and Compaction of Replacement Heart Valve

FIGS. 5A-D illustrate another embodiment of a replacement heart valve10″. The illustrated replacement heart valve 10″ is designed to replacea diseased native mitral valve. The replacement heart valve includes aself-expanding frame 20″ to which a valve body is attached. The valvebody includes an outer valve skirt 18″ and flexible leaflets that openand close, as discussed above. The replacement heart valve 10″ alsoincludes a plurality of fasteners, which connect the valve body to theframe 20, as will be described in more detail below.

The replacement heart valve 10″ generally has two configurations, anexpanded state shown in FIG. 5A and a compacted state shown in FIG. 5B.The replacement heart valve 10″ is typically stored in the compactedstate prior to usage. In addition, the replacement heart valve 10″ isgenerally mounted onto a delivery device to assume the compacted state.The compacted state is preferably sufficiently small in diameter to fitinto a catheter that will be used to advance the replacement heart valve10″ through the vasculature and access the heart for deployment.

The replacement heart valve 10″ is generally deployed to assume theexpanded state at a diseased or damage heart valve. Preferably thereplacement heart valve 10″ transitions from the compacted state to theexpanded state by self-expansion of the frame 20″. In some embodiments,the replacement heart valve 10″ transitions from a compacted to anexpanded state by expansion of the frame 20″ by a dilator, such as aballoon, or the like. The transition may also be performed by thecombination of a self-expanding frame and a dilator.

Expansion of the frame 20″ is controlled, at least in part, by thelongitudinal 56″ and undulating struts that make up the frame. Asmentioned previously, the replacement heart valve 10″ has anon-foreshortening portion 52″ and a foreshortening portion 54″. Theseportions can be defined at least in part by the frame 20″ and thepositioning of various types of struts along the frame 20″.

The illustrated upstream portion 38″ of the frame 20″ is also part ofthe non-foreshortening portion 52″. Longitudinal struts 56″substantially confine or restrict the upstream portion 38″ from changinglength upon the radial expansion or compaction of the frame 20″. Theupstream portion 38″ expands and compacts only in the radial direction.At least one ring 58″ of undulating struts can be positioned in theupstream portion 38″. Second and third rings 60″, 62″ are also shown.The at least one ring 58″ of undulating struts can extendcircumferentially in a zigzag formation around the frame. Each ring canhave two or more struts positioned between adjacent longitudinal struts56″. This allows the struts of the ring, as well as the longitudinalstruts 56″ to move closer together, or farther apart, as the replacementheart valve 10″ is respectively compacted, or expanded.

The longitudinal struts 56″ can also extend into the transition portion40″ between the upstream portion 38″ and the downstream portion 42″. Thetransition portion 40″ defines a transition from the smaller upstreamdiameter to the larger downstream diameter of the replacement heartvalve 10″ when in the expanded state. In the illustrated embodiment thelongitudinal struts 56″ flare radially outwardly in the transitionportion 40″. As such, the frame 20″ is generally divided into theupstream portion 38″ made up of the first diameter, the transitionportion 40″ at which the diameter is expanding, and the downstreamportion 42″ with the larger second diameter.

The downstream portion 42″ can also include at least one ring 64″ ofundulating struts. As shown in FIGS. 5A and 5B, the frame 20″ has tworings 64″ and 66″ that form substantially diamond- or oval-shaped cells.FIG. 5A illustrates nine cells disposed circumferentially about theframe 20″; however, any quantity of cells can be implemented in theframe.

Each illustrated cell has two downstream struts 46, 48 and two upstreamstruts 68, 70. The individual cells are coupled to one another atjunctions 72 located where one downstream strut 48 and one upstreamstrut 70 of one cell meet with one downstream strut 46 and one upstreamstrut 68 of another adjoining cell. The downstream undulating struts 46,48 join to form downstream apex 74. The upstream undulating struts 68,70 join to form upstream apex 76.

These diamond- or oval-shaped cells formed by the fourth 64″ and fifth66″ rings in the downstream portion 42″ longitudinally expand when theframe is radially compacted and longitudinally shorten when the frame isradially expanded as can be seen in FIGS. 5C-5D. In the compacted stateof FIG. 5C, the junctions 72 are closer together than when in theexpanded state shown in FIG. 5D. The longitudinally opposing apices 74,76 are closest in the expanded state.

Thus, the fourth 64″ and fifth 66″ rings can make up the foreshorteningzone 54″. Expansion of the replacement heart valve 10″ causes the strutsof the fourth ring 64″ to move angularly farther apart such that theyare at a greater angle relative to one another. Thus, they move from arelatively vertical orientation to a more horizontal orientation. Thisalso causes the ring 64″ to shrink in vertical height. The fifth ringexhibits similar behavior when the valve 10″ expands. This movement ofthe fourth 64″ and fifth 66″ rings results in foreshortening of theframe 20″. It is to be understood that foreshortening can also beachieved with more or less rings of undulating struts, as well as withother configurations of the frame.

The positioning of the outer valve skirt 18″, plurality of leaflets 12″and/or other components of the valve body within and along the frame20″, as well as the materials of the different parts of the replacementheart valve 10″ can also affect how much expansion, compression, and/orforeshortening the replacement heart valve 10″ can experience. Inaddition, the frame, the components of the valve body, and/or theconnection(s) between the components of the valve body and the frame canbe configured to deal with differences in material properties such aselasticity, and stretchability between the frame and the components ofthe valve body. It should be clear that some of these differences can beconsiderations for dealing with the foreshortening, non-foreshortening,expansion, and compaction of the replacement heart valve 10″.

The outer valve skirt and leaflets are preferably made from tissue, suchas pericardium. Pericardium, like some other suitable valve skirtmaterials, is flexible but not particularly stretchable or otherwiseelastic. At the same time, the outer valve skirt and leaflets can bemade to accommodate and substantially correspond to the shape of theframe in the expanded configuration.

In some embodiments of replacement heart valve 10, such as that shown inFIGS. 1-3, a connection skirt 50 can be connected to the downstream end36 of the outer valve skirt 18. The connection skirt 50 can be made ofan elastic fabric and can typically be placed to correspond to theforeshortening portion 52 of the frame 20. In this way, the connectingskirt 50 can stretch or compact with the longitudinal lengthening andshortening incident to radially compacting and expanding the valve 10.In such embodiments, the downstream end 36 of the pericardium valveskirt 18 can be connected to the connection skirt 50 at acircumferentially-extending seam.

Applicants have found that a circumferential seam can bunch up when thereplacement heart valve 10 is compacted, thus limiting compaction of thevalve. FIGS. 5A-5D illustrate an embodiment of replacement heart valve10″ without any circumferential seams. This enables the replacementheart valve 10″ to be able to radially compact to a smaller diameter.

In the illustrated embodiment the outer valve skirt 18″ is fabricatedfrom one, two, three, or more longitudinally oriented pieces of tissuematerial, e.g., pericardium, or the like, that longitudinally span theframe length from the upstream end 14″ to the downstream end 16″.Preferably such longitudinal strips are stitched together bylongitudinally-extending seams. Such construction lends itself to makingthe outer valve skirt 18″ out of a single material and eliminates acircumferential stitch or seam joining sections of different materials.Thus, as mentioned, in the illustrated embodiment, there is nocircumferential stitch or other such connections to the valve skirt.

In the illustrated embodiment, the outer valve skirt 18″ is constructedof pericardium, which, like some other suitable valve skirt materials,is flexible but not particularly stretchable or otherwise elastic. Also,preferably the outer valve skirt 18″ is stitched to theexpanded-configuration frame 20″ so that the downstream end 36″ of theouter valve skirt 18″ is generally or nearly coextensive with thedownstream end 16″ of the frame 20″.

However, as noted above, when the implant is radially compacted, thelongitudinal length of the frame 20″ increases. As such, preferably thedownstream portion of the outer valve skirt 18″ is attached to the frame20″ in a manner that enables the frame 20″ to move relative to the outervalve skirt 18″. In this manner, when the foreshortening portion 54″increases in length, the outer valve skirt 18″ can remain substantiallythe same length, but the struts of the foreshortening cells can moverelative to the outer valve skirt 18″. In this way, the outer valveskirt material is not substantially stretched or damaged.

In a preferred embodiment, the outer valve skirt 18″ is attached to thenon-foreshortening portion 52″ of the frame 20″ in a manner so thatthere is little to no relative longitudinal movement between the frame20″ and the outer valve skirt 18″. The outer valve skirt 18″ can beattached to the frame with a number of fasteners. The fasteners can beany device that can secure two objects together and can include two ormore different types or different styles of device. Some examplefasteners include stitches, staples, rivets, etc. Generally in theembodiments shown herein, stitches are used to attach the outer valveskirt to the frame, as well as to attach other components to oneanother. It will be understood that these are simply example fastenersand other devices could also be used.

FIGS. 5A-5D illustrate a stitching arrangement in which the outer valveskirt 18″ is mounted to the frame 20″ at the downstream portion so as toallow some relative movement. The downstream portion of the outer valveskirt 18″ is mounted to the frame in the foreshortening portion 54″ withloose or semi-loose stitching 78, 80 that allows the outer valve skirt18″ to slide relative to the frame struts 46, 48, 68, 70. At the otherend, on the upstream portion the outer valve skirt 18″ can be mounted tothe frame 20″ with tight stitches 82, which are stitches or otherfasteners that are configured to substantially prevent longitudinalmovement of the outer valve skirt 18″ relative to the frame 20″ in thenon-foreshortening portion 52″.

The tight stitches 82 can be tightly looped and/or cross-stitched aroundthe struts 56″ and through the outer valve skirt 18″. The tight stitches82 can be disposed about the longitudinal struts 56″ at selectivelocations. As shown in FIGS. 5A and 5B, tight stitches 82 are positionedon the longitudinal struts 56″ adjacent the apices of the first ring 58″on the downstream side of the connected apices. This prevents the tightstitches 82 from migrating off of the upstream end of the frame 20″.Tight stitches 82 are also positioned adjacent the second 60″ and third62″ rings on the upstream side of the connected apices, preventing thetight stitches 82 from migrating toward the downstream end of thereplacement heart valve 10″.

Other arrangements are also contemplated. For example, in someembodiments, tight stitches 82 can be located on both the upstream anddownstream sides of the connected apices to prevent longitudinalmigration of the outer valve skirt 18″. In some embodiments, the tightstitches 82 can be looped through eyelets coupled to the upstream end ofthe longitudinal struts 56″ and/or selectively located along thelongitudinal struts. In still further embodiments, the tight stitches 82can extend along, or span, a portion and/or the full length of one ormore of the longitudinal struts 56″.

Loose stitches 78, 80 can be used to allow some relative movementbetween the outer valve skirt 18″ and the frame 20″ as best seen inFIGS. 5C and 5D. The loose stitches can come in two types, those 80 thatconnect the outer valve skirt 18″ to one strut and those 78 that connectthe outer valve skirt 18″ to two struts. A single strut stitch 80 loopsaround a single strut to couple the outer valve skirt 18″ to the frame20″. A double-strut stitch 78 loosely loops around a pair of struts nearthe junction 72 when in the expanded state. The double-strut stitch 78passes through the center of radially adjacent cells and the outer valveskirt tissue material.

The loose stitches 78, 80 have a greater distance between theirrespective points of entry into the outer valve skirt 18″ tissuematerial than the tight stitches 82. The loose stitches 78, 80 alsoprovide more room or space for strut movement relative to the outervalve skirt 18″. The loose stitches 78, 80 readily allow the outer valveskirt 18″ downstream end to float, or slide, relative to the frame 20″,yet also sufficiently and durably mount the outer valve skirt 18″ to theframe 20″. In some embodiments, stitches that may not be physicallyloose-fitting may be placed so as to allow the outer valve skirtdownstream end to float, or slide, relative to the frame. Such stitches,as well as physically loose stitches, can also be referred to asfloating stitches or sliding stitches.

The loose stitches 78, 80 can allow the outer valve skirt 18″ that islongitudinally shorter than the compacted frame to slide on the cellstruts as the cells foreshorten during radial expansion, as illustratedin the detail views of FIGS. 5C and 5D. Four struts 46, 48, 68, 70joined at each junction 72 radially expand from a compactedconfiguration in which the apices 74, 76 are relatively close to oneanother to an expanded configuration in which the apices 74, 76 arerelatively farther apart. The loose stitches 78, 80 are urged downstreamas the cells radially expand positioning the junctions 72 farther apart.

The double-strut stitch 78 is urged downstream because the distancebetween the apices 74, 76 and the upstream portions of the strutsbecomes wider than the stitch width and the stitch is urged toward thenarrower portion of the V- or X-shaped configuration. This can be seenby comparing the position of the double-strut stitch 78 in FIG. 5D withthat of FIG. 5C. The loose stitches “ride” the struts downstream totheir final longitudinal position, as indicated by the arrows. Thesingle stitch 80 also moves along the strut because of the movement ofthe double-strut stitch 78 and the outer valve skirt.

The positions of the loose stitches 78, 80 can be limited by theposition of either or both of the junction 72 and the apices 74, 76. Forexample, in FIG. 5C, the stitches 78, 80 cannot pass any lower than thejunction 72 and/or apices 74 of which they are positioned next to. Toposition the loose stitches 78, 80 lower than the junction 72 and/orapices 74, with the loose stitches 78, 80 still being around a strutwould overload the stitch upon expansion because the lengthening of theframe would force the stitch downstream into the junction or apex.

With reference now to FIGS. 6A and 6B, in another embodiment ofreplacement heart valve 10″′, the downstream end of the outer valveskirt 18″′ is connected to the struts in the downstream portion 42″′ bymultiple stitches 80′. In this embodiment, the downstream end 36″′ ofthe outer valve skirt 18″′ is shaped to correspond to the undulatingpattern of ring 66″′ when in the expanded state. However, as shown inFIG. 6A, the skirt is not attached to the downstream apices 76′ and isspaced therefrom. As such, when the replacement heart valve 10″′ iscompacted, the outer valve skirt 18″′ and stitches 80′ will slideupstream relative to the downstream struts, resulting in a longitudinalspace between the outer valve skirt distal end 36″′ and the distalapices 76′. When the foreshortening cell is compacted, the celllongitudinal length increases but the outer valve skirt length does not,resulting in a longitudinal space between the downstream apex 76′ andthe downstream end 36″′ of the outer valve skirt 18″′. The frame 20″′thus longitudinally expands while the outer valve skirt 18″′ maintainsits length.

FIGS. 7A-C illustrate still another embodiment of replacement heartvalve 10″″, in which the longitudinal length of the outer valve skirt18″″ skirt is generally the same, or substantially the same, as thelongitudinal length of the frame 20″″ in the radially-compactedconfiguration. In this embodiment, tight stitches 82″ can be used in theboth the non-foreshortening portion 52″″ and the foreshortening portion54″″. The long outer valve skirt 18″″ configuration preferably extendsfrom the compacted frame upstream end to the compacted frame downstreamend. The outer valve skirt 18″″ downstream end 36″″ can be securelycoupled, or stitched, to the frame downstream end 16″″ in a manner thatthe outer valve skirt 18″″ will substantially move with the frame 20″″as the frame longitudinally expands and contracts.

The outer valve skirt 18″″ can be greater in length than the length ofthe expanded-state frame and substantially the same length as thecompact frame. This can result in excess outer valve skirt material whenthe replacement heart valve is in the expanded configuration. The excesslength of the outer valve skirt 18″″ can create circumferential folds84, or material bunching, in the foreshortening portion of the frame, asdepicted in FIGS. 7A and 7C.

FIG. 7C illustrates a cross-section side view of the implant tissuematerial in this embodiment positioned in the frame downstream end afterthe frame expands radially outward. Preferably the folding or bunchingpattern can be selectively controlled by placement of stitches such asstitches at the junction 72″. It should be understood that, in otherembodiments, the valve skirt can be shorter, longer, or any lengththerebetween, than the illustrated long configuration. A longer skirtthan the long configuration skirt of FIG. 7C creates a greater numberand/or size of circumferential folds.

Also illustrated in FIGS. 7A-7C are eyelets 73. The eyelets 73 can beused to attach to the outer valve skirt to the frame. In someembodiments, the downstream anchors 24″″ can be passed through theeyelets 73 when assembling the replacement heart valve 10″″. Stitchingcan also pass through the eyelets 73. The eyelets 73 can also reinforcethe skirt material.

With continued reference to FIG. 7C, when the replacement heart valve10″″ is installed in the body, the folds 84 in the valve skirt materialpreferably are positioned at or adjacent the native valve annulus. Thus,over time the folds can support tissue ingrowth, further securing thereplacement heart valve 10″″ to the mitral valve native annulus andpreventing leakage past the outer valve skirt 18″″.

Delivery Device and Method

With reference next to FIG. 8, a schematic representation of thereplacement heart valve 10 as discussed above in connection with FIGS. 1and 2 is depicted installed in a human heart 90. The heart is shown incross-section, and represents typical anatomy, including a left atrium86 and left ventricle 88. The left ventricle 88 is defined by a muscularwall 98. The left atrium 86 and left ventricle 88 communicate with oneanother through a mitral annulus 92. Also shown schematically in FIG. 8is a native anterior mitral leaflet 94 having chordae tendineae 96 thatconnect a downstream end of the anterior mitral leaflet 94 to the musclewall 98 of the left ventricle 88. A left ventricle outflow tract 99extends toward the top of the left ventricle 88.

As shown, the replacement heart valve 10 is disposed so that the mitralannulus 92 is grasped between the upstream anchors 22 and the downstreamanchors 24. As such, all or most of the replacement heart valve 10extends into the left atrium 86. The portion of the replacement heartvalve 10 disposed upstream of the annulus 92 can be referred to as beingpositioned supra-annularly. The portion generally within the annulus 92is referred to as positioned intra-annularly. The portion downstream ofthe annulus is referred to as being positioned sub-annularly. In theillustrated embodiment, only a part of the foreshortening portion ispositioned intra-annularly or sub-annularly, and the rest of thereplacement heart valve 10 is supra-annular.

The following is an example of how the replacement heart valve 10 can bedeployed at a patient's native mitral valve annulus with reference toFIG. 8. A radially-compacted replacement heart valve 10 is advanced on adelivery device through and past the mitral valve annulus 92 so that thedownstream anchors 24 are positioned downstream of the native mitralvalve leaflets 94. The heart valve 10 can be partially deployed so thatthe downstream portion of the replacement heart valve 10 can be allowedto self-expand, thus urging the downstream anchors 24 between thechordae tendineae 96 and radially outboard of the native mitral valveleaflets 94. The delivery device and replacement heart valve 10 can thenbe proximally retracted or moved upstream to engage the downstreamanchors 24 with the downstream side of the native mitral valve annulus92. In this motion, preferably the downstream anchors 24 engage andcapture the native leaflets 94. Once the native leaflets are engaged andcaptured by the anchors 24, the remainder of the replacement heart valve10 can then be deployed to allow self-expansion of the replacement heartvalve 10 so that the upstream anchors 22 engage the upstream side of thenative annulus 92, and the replacement heart valve 10 is deployed inoperational condition. In some embodiments the replacement heart valvemay not be self expanding, ant the partial and full deployment may beaccomplished by one or more inflatable balloons or the like.

Replacement heart valves can be delivered to a patient's heart mitralvalve annulus in various ways, such as by open surgery,minimally-invasive surgery, and percutaneous or transcatheter deliverythrough the patient's vasculature.

With reference to FIGS. 9A-B, an embodiment of a delivery device 100 isshown in connection with a replacement heart valve 10. The illustratedembodiment comprises an elongate, delivery catheter configured to beadvanced through a patient's vasculature in a percutaneous deliveryapproach. The delivery device 100 can be a spring or a cut metalhypotube that imparts rigidity to the device and yet allows flexibilityto be able to pass through the curvosities of the vasculature. Thedelivery device 100 can also be covered with a polymer outer sheath.

The illustrated delivery device 100 comprises an elongate inner tube 102that is attached at its distal end to a nose cone 104. The inner tube102 has a lumen sized and configured to slidably accommodate a guidewire106 so that the delivery device 100 can be advanced over the guidewirethrough the vasculature. The delivery device 100 may also be a steerablecatheter which may or may not use a guidewire.

As can best be seen in FIG. 9B, an inner retention ring 112 can bepositioned on the inner tube 102. A support tube or outer retention ring108 concentrically encircles the inner tube 102 and is sized to beslidable over the inner tube and the inner retention ring. In theillustrated embodiment the support tube is elongate. An outer sheath 110is disposed so as to be slidable over the support tube 108.

In the illustrated embodiment, and preferably, in a manner as discussedin embodiments presented below, the support tube or outer retention ring108 and outer sheath 110 cooperate to grasp onto the replacement heartvalve 10. FIG. 9B schematically shows a valve frame 20 within andsecured by the outer sheath 110 and other components of the deliverydevice 100. The inner retention ring 112 is also shown engaging theproximal end 14 of the valve frame 20. For example, teeth 116 on theinner retention ring 112 can engage tabs 15 on the proximal end 14 ofthe valve frame 20. The outer retention ring 108 can be positioned overthe inner retention ring 112 so that the proximal end of the replacementheart valve 10 is trapped therebetween, securely attaching it to thedelivery device 100.

The outer sheath 110 can also be positioned over the distal end of thedelivery device 100 and over the replacement heart valve 10. As shown,the outer sheath 110 is advanced over a portion of the nose cone 104 ofthe delivery device 100. Optionally, a retainer member 114, e.g., ano-ring, a clamp, a cover, or the like, can be used to retain the outersheath 110 in place. As shown, an o-ring 114 is placed over the outersheath 110 at a groove or slot 118 disposed circumferentially around thenose cone 104. In some embodiments, the nose cone can include a flangethat encompasses and secures the outer sheath, so that the outer sheathfits into the nose cone under the flange. This flange may also cover allor part of the replacement heart valve. In some embodiments, thedelivery device may include one or more additional sheaths or otherfeatures that can be advanced over all or part of the replacement heartvalve.

The delivery device 100 is configured to retain and restrict the valveframe 20 and the replacement heart valve 10 from expanding. The deliverydevice 100 restrains the replacement heart valve 10 until thereplacement heart valve 10 is deployed from the delivery device 100 at,or adjacent, the native mitral valve annulus 92.

With reference next to FIGS. 10A-10C and FIG. 8, an embodiment of amethod and apparatus for deploying a replacement heart valve 10 isdepicted. Referring to FIG. 10A, it can be seen that the replacementheart valve 10, mounted in a radially-compacted configuration on thedistal end of the delivery device 100, is introduced into the leftatrium 86 of the heart 90. As shown, the native mitral leaflets 94(posterior leaflet shown) extend downstream of the native annulus 94,and chordae tendineae 96 extend downstream from the mitral valve to theventricle wall.

With reference next to FIG. 10B, the delivery device 100 is advanced sothat the replacement heart valve 10 is positioned slightly downstream ofits final mounting point. More specifically, it is positioned so thatthe downstream anchors 24 are positioned downstream of where the chordaetendineae 96 connect to the free end of the native mitral valve leaflets94.

The outer sheath 110 is then at least partially retracted to expose atleast part of the downstream end of the replacement heart valve 10,including the downstream anchors 24 as shown in FIG. 10C. The downstreamend of the replacement heart valve 10 radially expands to approximatelythe full extent, or slightly less than the full extent. At the sametime, the upstream end of the replacement heart valve 10 is stillretained by the delivery device and is at least partially radiallycompacted. During expansion of the downstream end of the replacementheart valve 10 the downstream anchors 24 pass between chordae tendineae96 so that the upstream-directed downstream anchor tips 28 substantiallyface the downstream side of the native mitral valve annulus 92. As theupstream portion of the replacement heart valve 10 is still retained bythe delivery device 100 in a partially radially-compacted state, theposition of the replacement heart valve 10 can still be readilyadjusted.

After the downstream anchors 24 are expanded to be positioned downstreamof and radially outside of the native leaflets 94, the delivery device100 and replacement heart valve 10 are moved in an upstream direction.This causes the downstream anchors 24 and anchor tips 28 to engage withthe downstream side of the native annulus 92, and the native leaflets94. The native leaflets 94 are engaged and possibly retracted by theanchors. In some embodiments, the anchors pull the native leaflets 94proximally, resulting in the native leaflets 94 being bunched up, andthe chordae tendineae 96 being stretched and/or tightened. In otherembodiments the native leaflets 94 may not be bunched up or may be onlypartially bunched up, but are contained by the anchors so as to preventmovement of the leaflets 94 into, for example, the left ventricleoutflow tract 99.

Once the downstream anchors 24 are properly placed, the delivery device100 can release the upstream anchors 22 and the remaining upstream end14 of the replacement heart valve 10. This can be done by retracting theouter retention ring 108. In some embodiments this can be done by fullyretracting the outer sheath 110, as well as, the outer retention ring108.

As discussed previously, the upstream anchors 22 flare radially outwardunder the self-expansion force of the frame 20 and advance toward theupstream side of the native mitral valve annulus 92 under theforeshortening force of the cells. The downstream 24 and upstream 22anchors can thus securely grasp the native mitral valve annulus 92between their opposingly directed anchor tips, and the replacement heartvalve 10 is fully and securely installed as can be seen in FIG. 8. Theanchor placement can preferably prevent or reduce the prevalence of anyup and/or down motion of the frame. The anchor placement can also helpensure that the replacement heart valve is perpendicular to the annulusand prevents any “rocking” and/or tilting of the frame. By engaging boththe native annulus 92 and the native leaflets 94 by the frame 20 andanchors 22, 24 the load can be more evenly distributed to achieveequilibrium. Such a configuration can also provide a more robustimplantation.

The independent nature of each anchor can allows the frame to conform toa number of different shapes. For example, the three dimensional annularshape of the mitral valve may not be entirely flat, and in fact, as isthe case with most mitral anatomy, may be more saddle shaped. Thus, theindependent anchors can stretch and bend to be able to engage thesedifferent shapes.

In embodiments in which the native leaflets 94 are compacted and urgedagainst both the outer surface of the replacement heart valve 10 and thenative annulus 92, the bunched up leaflets advantageously providesadditional leak prevention between the native tissue and the replacementheart valve 10, or between the anchors and the valve frame.

Referring now FIG. 11, another embodiment of delivery device 100′ isshown. Numerical reference to components is the same as previouslydescribed, except that a prime symbol (′) has been added to thereference. Where such references occur, it is to be understood that thecomponents are the same or substantially similar to previously-describedcomponents. The illustrated embodiment comprises an elongate, deliverycatheter configured to be advanced through a patient's vasculature in apercutaneous delivery approach. In addition to an outer sheath 110′ andan outer retention ring 108′, the delivery device 100′ can also includea secondary sheath 120.

The secondary sheath 120 can be slidable over the outer retention ring108′ which is slidable over the inner tube 102′ and the inner retentionring 112′. The outer sheath 110′ is disposed so as to be slidable overboth the support tube 108′ and the secondary sheath 120. The outerretention ring 108′, secondary sheath 120 and outer sheath 110′ allcooperate to grasp onto the replacement heart valve 10. FIG. 11schematically shows a valve frame 20 within and secured by these threecomponents.

The secondary sheath 120 can be advanced over all or a part of thereplacement heart valve 10. As such, the secondary sheath 120 can beused to further control the expansion of the replacement heart valve 10during the delivery process. For example, the secondary sheath 120 canbe positioned so that the distal end is right next to but not coveringthe downstream anchors 24. Thus, when the outer sheath 110′ iswithdrawn, the secondary sheath 120 can limit the expansion of thereplacement heart valve 10. In some embodiments, the secondary sheath120 can limit the expansion of the replacement heart valve 10 to justthe downstream anchors 24 or just the downstream anchors and a smallamount of radial expansion of the foreshortening cells.

In some embodiments, the secondary sheath 120 can be positioned at thebase of the downstream anchors 24 such that the secondary sheath 120 isbetween the downstream anchors 24 and the rest of the frame 20. Thus,the secondary sheath 120 can cover the frame 20 essentially to thedistal end 16, with primarily only the downstream anchors 24 exposed.Again, this can limit the expansion of the replacement heart valve 10upon withdrawal of the outer sheath 110′.

The delivery methods described above with reference to delivery device100 and FIGS. 10A-C can be considered a two stage delivery method; thefirst stage being withdrawal of the outer sheath 110, and the secondstage being withdrawal of the outer retention ring 108. The deliverydevice 100′ can use a three stage delivery method as will be describedbelow. It should be understood that both delivery devices 100, 100′ canalso be used in other delivery methods that may be considered singlestage, two stage, three stage, etc.

The delivery device 100′ can be used in a delivery procedure similar tothat described above. The delivery device 100′ can have a replacementheart valve 10 mounted in a radially-compacted configuration on thedistal end and be introduced into the left atrium 86 of the heart 90.The delivery device 100′ can be advanced to position the replacementheart valve 10 slightly downstream of its final mounting point. Morespecifically, the replacement heart valve 10 can be positioned so thatthe downstream anchors 24 are positioned downstream of where the chordaetendineae 96 connect to the free end of the native mitral valve leaflets94.

The outer sheath 110′ can then be at least partially retracted to exposeat least the downstream anchors 24. The secondary sheath 120 and outerretention ring 108′ can still be positioned over the replacement heartvalve 10 to limit expansion of the replacement heart valve 10 afterwithdrawal of the outer sheath 110.

With the downstream anchors 24 exposed and little to no other expansionexperienced, the delivery device 100′ can easily position the downstreamanchors 24 in an initial desired position. The secondary sheath 120 canthen be retracted allowing the replacement heart valve 10 to furtherexpand while still being attached at the proximal end 14 to the deliverydevice 100′ at the inner 112 and the outer 108 retention rings. Thereplacement heart valve 10 can then be adjusted again prior tocompletely releasing the replacement heart valve 10 from the deliverydevice 100′.

In some embodiments, the downstream anchors 24 can be positioned firstnext to one part of the native valve annulus before the secondary sheath120 is withdrawn. As the mitral valve is a bicuspid valve, the deliverydevice 100′ can be used to attach the downstream anchors 24 to one ofthe leaflets, such as the posterior leaflet and then to the other of theleaflets, such as the anterior leaflet. This second part can be doneafter the replacement heart valve 10 is expanded or further expanded bymoving the secondary sheath 120. In some embodiments, staged deploymentcan also be achieved without the use of a secondary sheath. For example,a primary sheath with sufficient column strength and/or resistance tocollapsing/corrugating/compression along the axis can be used to achievestaged deployment.

In some embodiments, the entrance route of the delivery device 100′ intothe left atrium 86 can bias the delivery device 100′ towards one side ofthe mitral valve 92. For example, the delivery device 100′ may be biasedtowards the posterior leaflet of the mitral valve 92. Also, an axis ofthe delivery device may be angled relative to an axis of the nativeannulus. This can facilitate securing the downstream anchors 24 to theposterior side or the posterior leaflet first, prior to expanding orfurther expanding the replacement heart valve 10. The downstream anchors24 can then be secured to the anterior side of the mitral valve 92 or tothe anterior leaflet.

For example, the downstream anchors 24 can be positioned initially pastthe mitral valve annulus 92 and then moved upstream to engage one sideand/or one leaflet. The delivery device 100′ can then be repositioned,or first the secondary sheath 120 removed then the delivery device 100′repositioned. The delivery device 100′ can again be moved upstream, thistime so that the downstream anchors 24 on the other side will alsoengage the other side of the mitral valve 92 and/or the other leaflet.

After the downstream anchors 24 are released the delivery device 100′and replacement heart valve 10 are moved in an upstream direction. Thiscauses the downstream anchors 24 and anchor tips 28 to engage with thedownstream side of the native annulus 92, and the native leaflets 94.The native leaflets 94 are engaged and possibly retracted by theanchors. As mentioned, this can occur first on one side or to oneleaflet and then to the other side or to the other leaflet.

Once the downstream anchors 24 are properly placed, the delivery device100′ can then release the upstream anchors 22 and the remaining upstreamend 14 of the replacement heart valve 10. This can be done by retractingthe outer retention ring 108′. In some embodiments this can be done byretracting the outer retention ring 108′ as well as fully retracting oneor more of the outer sheath 110′ and the secondary sheath 120.

As discussed previously, the upstream anchors 22 flare radially outwardunder the self-expansion force of the frame 20 and advance toward theupstream side of the native mitral valve annulus 92 under theforeshortening force of the cells as the cells complete their radialexpansion. The downstream 24 and upstream 22 anchors thus securely graspthe native mitral valve annulus 92 between their opposingly directedanchor tips, and the replacement heart valve 10 is fully and securelyinstalled as can be seen in FIG. 8.

Multi-stage release of the replacement heart valve 10 by the deliverydevice 100, 100′ can facilitate better control and positioning of thereplacement heart valve 10 at the native annulus 92. As explained above,three stage release by the delivery device 100′ can allow for a quickerand more reliable securement of the replacement heart valve 10 to themitral valve 92.

A delivery device 100, 100′ with one or more of an outer sheath, asecondary sheath and/or an outer retention ring can control theirmovement in different ways. For example, each or some of the outersheath, secondary sheath and outer retention ring can move separatelyand independently from the others. Alternatively, or in addition, somecan be moved together, such as being attached to move in a coordinatedfashion.

For example, the secondary sheath can be attached to the outer sheaththrough sutures, stitches, wire, string, cable, band, ribbon, etc. Thiscan allow the outer sheath to be withdrawn initially without affectingthe positioning of the secondary sheath. The outer sheath can then befurther removed, causing tension on the secondary sheath throughwhichever device has been used to attach the two. Thus, the secondarysheath can be a floating sheath. In some embodiments, internal wires orouter coverings may extend the length or substantially the length of thedelivery device and can be actuated at the proximal end.

In another embodiment, the outer sheath can be folded over itself in oneor more positions to take the place of a secondary sheath and/or anouter retention ring. For example, the distal end of the outer sheathcan be positioned over the inner retention member and then the outersheath can be folded over itself to cover the replacement heart valve.Initial movement of the outer sheath can uncover a part of thereplacement heart valve without uncovering the inner retention member.

In still another embodiment, the nose cone can be used to cover aportion of the replacement heart valve such as the downstream anchors.The nose cone can include a flange that encompasses and secures theouter sheath, so that the outer sheath fits into the nose cone under theflange. This flange may cover all or part of the replacement heartvalve. The nose cone can be advanced exposing and expanding the anchors.The outer sheath can cover the rest of the device and can then be laterwithdrawn similar to the secondary sheath.

Although this invention has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the present invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the invention and obvious modifications and equivalentsthereof. In addition, while a number of variations of the invention havebeen shown and described in detail, other modifications, which arewithin the scope of this invention, will be readily apparent to those ofskill in the art based upon this disclosure. For example, the supportband can be used with the replacement heart valves shown in FIGS. 1-3,5A-7C. Also, connection skirt can be used with the replacement heartvalve shown in FIG. 4. Further, additional embodiments of valve deliverydevices, whether or not disclosed herein, may employ, for example, thetwo and three-stage delivery methods discussed herein. It is alsocontemplated that various combinations or sub-combinations of thespecific features and aspects of the embodiments may be made and stillfall within the scope of the invention. Accordingly, it should beunderstood that various features and aspects of the disclosedembodiments can be combined with or substituted for one another in orderto form varying modes of the disclosed invention. Thus, it is intendedthat the scope of the present invention herein disclosed should not belimited by the particular disclosed embodiments described above, butshould be determined only by a fair reading of the claims that follow.

Similarly, this method of disclosure, is not to be interpreted asreflecting an intention that any claim require more features than areexpressly recited in that claim. Rather, as the following claimsreflect, inventive aspects lie in a combination of fewer than allfeatures of any single foregoing disclosed embodiment. Thus, the claimsfollowing the Detailed Description are hereby expressly incorporatedinto this Detailed Description, with each claim standing on its own as aseparate embodiment.

What is claimed is:
 1. An implantable prosthetic valve comprising: anannular frame comprising an upstream portion and a downstream portionand being radially collapsible and expandable between a radiallycollapsed configuration and a radially expanded configuration, whereinthe frame comprises a plurality of struts; a leaflet structurepositioned within the frame and secured thereto; and an outer skirtcomprising a first portion that is tightly connected to the frame withfirst stitches such that the first portion is prevented from movingaxially with respect to the frame when the frame radially expands andcollapses and a second portion that is loosely connected to the framewith second stitches such that the second portion can move axially withrespect to the frame when the frame radially expands and collapses, andwherein at least one of the second stitches is connected to two strutsof the frame.
 2. The prosthetic valve of claim 1, wherein the at leastone of the second stitches is configured such that it slides along thetwo struts of the frame when the frame is radially expanded andcollapsed.
 3. The prosthetic valve of claim 1, wherein the framecomprises a plurality of undulating struts arranged in rings positionedalong the length of the frame, and wherein the at least one of thesecond stitches is looped around two adjacent undulating struts of thesame ring.
 4. The prosthetic valve of claim 1, wherein the framecomprises a plurality of longitudinal struts and a plurality ofundulating struts, and wherein at least one of the first stitches isconnected to a longitudinal strut.
 5. The prosthetic valve of claim 1,wherein at least one of the second stitches is connected to a singlestrut of the frame.
 6. The prosthetic valve of claim 1, wherein at leastone of the first stitches is connected to a single strut of the frame.7. The prosthetic valve of claim 1, wherein the outer skirt comprises anon-stretchable material.
 8. The prosthetic valve of claim 1, whereinthe second stitches are configured such that they are forced to move inan axial direction relative to the frame when the frame radiallyexpands.
 9. The prosthetic valve of claim 1, wherein the first portionof the outer skirt comprises an upstream portion and the second portionof the outer skirt comprises a downstream portions.
 10. An implantableprosthetic valve comprising: an annular frame comprising an inflow endand an outflow end and being radially collapsible and expandable betweena radially collapsed configuration and a radially expandedconfiguration; a plurality of valve leaflets positioned within the frameand secured thereto; and an outer skirt comprising a first portion thatis secured to the frame such that the first portion is prevented frommoving relative to the frame when the frame radially expands andcollapses, the outer skirt further comprising a second portion axiallyspaced from the first portion along a length of the outer skirt, thesecond portion being loosely connected to the frame with stitches suchthat the second portion can move relative to the frame when the frameradially expands and collapses, and wherein at least one of the stitchesis connected to two struts of the frame.
 11. The prosthetic valve ofclaim 10, wherein the at least one of the stitches is configured toslide with the second portion of the outer skirt along the two struts ofthe frame when the frame is radially expanded and collapsed.
 12. Theprosthetic valve of claim 10, wherein the frame comprises a plurality ofcircumferentially extending rows of undulating struts, wherein the atleast one of the stitches is looped around two adjacent undulatingstruts of the same row.
 13. The prosthetic valve of claim 10, whereinthe first portion of the outer skirt is secured to the frame by tightstitches.
 14. The prosthetic valve of claim 10, wherein another one ofthe stitches is connected to a single strut.
 15. The prosthetic valve ofclaim 10, wherein the another one of the stitches forms multiple loopsextending around the single strut and through the first portion of theouter skirt.
 16. The prosthetic valve of claim 10, wherein the outerskirt comprises a non-stretchable material.
 17. The prosthetic valve ofclaim 10, wherein the first portion of the outer skirt comprises aninflow end portion of the skirt and the second portion of the outerskirt comprises an outflow end portion.
 18. An implantable prostheticvalve comprising: an annular frame comprising an upstream portion and adownstream portion and being radially collapsible and expandable betweena radially collapsed configuration and a radially expandedconfiguration, wherein the frame comprises a plurality of struts; aleaflet structure positioned within the frame and secured thereto; andan outer skirt comprising an upstream portion and a downstream portion,wherein the upstream portion is connected to the frame with firststitches such that the upstream portion of the outer skirt is preventedfrom moving axially with respect to the frame when the frame radiallyexpands and collapses and the downstream portion is connected to aforeshortening portion of the frame with second stitches such that theupstream portion of the outer skirt can move axially with respect to theframe when the frame radially expands and collapses, and wherein atleast one of the second stitches is connected to two struts of the framethat can slide axially relative to the two struts when the frameradially expands and collapses.
 19. The prosthetic valve of claim 18,wherein the at least one of the second stitches loosely wraps around twostruts adjacent a junction between the two struts.
 20. The prostheticvalve of claim 18, wherein at least one of the first stitches isconnected to a single strut of the frame.